Registration Dossier

Administrative data

Endpoint:
water solubility
Type of information:
(Q)SAR
Adequacy of study:
key study
Study period:
November 2009
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Estimation for the Reference Substance performed by a method recommended by REACH Guidance (R7.A, pg 91).
Justification for type of information:
QSAR prediction: migrated from IUCLID 5.6

Data source

Reference
Reference Type:
other: WSKOW output
Title:
Unnamed
Year:
2013
Report Date:
2013

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
WSKOW uses a "fragment constant" methodology to predict log P.  In a "fragment constant" method, a structure is divided into fragments (atom or larger functional groups) and coefficient values of each fragment or group are summed together to yield the log P estimate.  Further details on the methodology, accuracy and applicability domain are available in section entitled "overall remarks and attachement" using the QSAR Model Reporting Format.
GLP compliance:
no
Type of method:
other: Estimated

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: SMILE notation
Details on test material:
- SMILE notation: CC(O)COC(=O)c1c(Br)c(Br)c(Br)c(Br)c1C(=O)OCCOCCO

Results and discussion

Water solubility
Water solubility:
0.057 mg/L
Temp.:
25 °C
Remarks on result:
other: pH not specified by software program.
Details on results:
pH not specified by software program.

Any other information on results incl. tables

The registered substance (CAS # 20566-35-2) involves the heating and subsequent reaction of Tetrabromophthalic Anhydride (TBPA) with Di-Ethylene Glycol (DEG) and Propylene Oxide (PO). The nature of the reagents involves the formation of a complex mixture of products with different combinations of these 3 reagents. Current, QSAR models cannot test UVCB substances. Therefore, the QSAR has been performed on the major product which is also the structure with the lowest molecular weight (1 unit of region of TBPA, 1 DEG and 1 PO). In terms of predicted toxicology, it can reasonably be assumed that the structure having the lowest molecular weight should be the most bioavailable. Based on this toxicity principle, QSAR analyses were performed using the SMILE structure of the smallest molecular weight structure which is also the major product of the mixture (identified at 26% area by HPLC).

In addition, same model has been ran with SMILE notation of 1 unit of TBPA, 1 DEG and with 2 or 3 PO (See below SMILE notation and parameters) and same order of magnitude was found for these 2 moldecules presenting 1 unit of TBPA. In contrast, when looking at the results for 2 units of TBPA, values are dramatically decreasing but parameters are outside of the model boundaries limits.

*Smile notation for 1 unit of TBPA, 1 DEG and 2 PO:

C(=O)(c1c(C(=O)OCC(C)OCC(C)O)c(Br)c(Br)c(Br)c1Br)OCCOCCO

Parameters:

Mol For: C18 H22 Br4 O8

Mol Wt: 685.99

Log Kow (KOWWIN v1.68): 3.97

WS: 0.01774 mg/L

*Smile notation for 1 unit of TBPA, 1 DEG and 3 PO:

C(=O)(c1c(C(=O)OCC(C)OCC(C)OCC(C)O)c(Br)c(Br)c(Br)c1Br)OCCOCCO

  Parameters:

Mol For: C21 H28 Br4 O9

Mol Wt: 744.07

Log Kow (KOWWIN v1.68): 4.11 WS: 0.005485 mg/L

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): insoluble (< 0.1 mg/L)
The estimated water solubility is 0.05697 mg/L.
Executive summary:

The estimated water solubility is 0.05697 mg/L.